1. Polarimeter Detectors for 12 GeV Hall C GEn measurements
Experiment E
Jlab Collaboration Meeting October 2013

2. A. Semenov, 2012 Geometry

3. Plan A (100 cm detectors)

4. Plan B (160 cm detectors)

5. Detectors needed for proton-recoil polarimeter
  28 scatterers   10 x 10 x 100 cm   56 Up & Down Detectors
= 84 Detectors

6. Detectors Available Neutron Detectors: 32 10 x 10 x 100 cm in HAND
x 10 x 100 cm at KSU 34   4 x 5 x 40 in  in HAND
68 Total
~80 10 x 10 x 160 cm from Hall A GEn
So need 16 more 10 x 10 x 100 cm for Plan A
Plan B OK, using the 160 cm detectors
Additionally, there exists: (could be cut and machined)  8     4 x 20 x 40 in      detectors at KSU 3     4 x 10 x 40 in      detectors at KSU
4 x 10 x 40 in detectors in HAND
16 10 x 22.5 x 400 cm detectors from BLAST
Veto Detectors: (Hall C) + 24 (Hand) + ??

7. Electronic Channels needed
  Plan A: 28 scatterers + 28 up/dn detectors
2 ends/det = 112 channels   Plan B: 28 scatterers + 56 up/dn detectors
2 ends/det = 168 channels
Plus Vetoes

8. Phototubes and Magnetic Shields
All existing detectors have PMTs and Mag Shields
However, many of the PMT’s are old or known to not be “good.”
The 10 x 10 x 100 cm detectors have 2-in PMTs
The 4 x 5 x 40 in detectors have 5-in PMTs